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At least 217 records · Page 12Linked to original sources
USGS2020

A review of pathogens, diseases, and contaminants of muskrats (Ondatra zibethicus) in North America

Over the last 50 years, significant muskrat (Ondatra zibethicus) harvest declines have been observed throughout North America. Several theories for the decline have been proposed, including increased parasite infections and disease within muskrat populations. No existing wholistic review of muskrat exposure to pathogens, contaminants, and diseases exists. To address this knowledge gap, we conducted a thorough review of existing literature on muskrat pathogens, contaminants, and diseases across their natural range. This review is comprised of 129 articles from 1915-2019and from 27 U.S. states and 9 Canadian provinces. A wide diversity of contaminants, toxins, and pathogens were reported in muskrats, with the most common diseases being cysticercosis, tularemia, Tyzzer’s disease, and biotoxin poisoning from cyanobacteria. This review provides a summary of muskrat pathogens, contaminants, and disease over a century that has observed significant population declines throughout the species’ range in North America. Such data provides baseline data for understanding the potential role of disease in these declines. In addition, these data highlight critical knowledge gaps that warrant future research efforts.

Alaska, Alberta, British Columbia, Colorado, Idaho↗
USGS2019

Asian swamp eels in North America linked to the live-food trade and prayer-release rituals

We provide a history of swamp eel (family Synbranchidae) introductions around the globe and report the first confirmed nonindigenous records of Amphipnous cuchia in the wild. The species, native to Asia, is documented from five sites in the USA: the Passaic River, New Jersey (2007), Lake Needwood, Maryland (2014), a stream in Pennsylvania (2015), the Tittabawassee River, Michigan (2017), and Meadow Lake, New York (2017). The international live-food trade constitutes the major introduction pathway, a conclusion based on: (1) United States Fish and Wildlife Service’s Law Enforcement Management Information System (LEMIS) database records revealing regular swamp eel imports from Asia since at least the mid-1990s; (2) surveys (2001–2018) documenting widespread distribution of live A. cuchia among ethnic food markets in the USA and Canada; (3) indications that food markets are the only source of live A. cuchia in North America; and (4) presence of live A. cuchia in markets close to introduction sites. Prayer release appears to be an important pathway component, whereby religious practitioners purchase live A. cuchia from markets and set them free. Prevalence of A. cuchia in US markets since 2001 indicates the species is the principal swamp eel imported, largely replacing members of the Asian complex Monopterus albus/javanensis. LEMIS records (July 1996–January 2017) document 972 shipments containing an estimated 832,897 live swamp eels entering the USA, although these data underestimate actual numbers due to undeclared and false reporting. LEMIS data reveal most imports originate in Bangladesh, Vietnam, and China. However, LEMIS wrongly identifies many imported swamp eels as “Monopterus albus”; none are identified as A. cuchia although specimens from Bangladesh and India are almost certainly this species. Some imported A. cuchia are erroneously declared on import forms as Anguilla bengalensis. To date, there is no evidence of A. cuchia reproduction in open waters of North America, presumably because it is a tropical-subtropical species and all introductions thus far have been in latitudes where winter water temperatures regularly fall near or below freezing.

Aquatic Invasions↗
USGS2016

Inference of population structure and demographic history in Taxodium distichum , a coniferous tree in North America, based on amplicon sequence analysis

PREMISE OF THE STUDY: Studies of natural genetic variation can elucidate the genetic basis of phenotypic variation and the past population structure of species. Our study species, Taxodium distichum , is a unique conifer that inhabits the flood plains and swamps of North America. Morphological and ecological differences in two varieties, T. distichum var. distichum (bald cypress) and T. distichum var. imbricarium (pond cypress), are well known, but little is known about the level of genetic differentiation between the varieties and the demographic history of local populations. METHODS: We analyzed nucleotide polymorphisms at 47 nuclear loci from 96 individuals collected from the Mississippi River Alluvial Valley (MRAV), and Gulf Coastal populations in Texas, Louisiana, and Florida using high-throughput DNA sequencing. Standard population genetic statistics were calculated, and demographic parameters were estimated using a composite-likelihood approach. KEY RESULTS: Taxodium distichum in North America can be divided into at least three genetic groups, bald cypress in the MRAV and Texas, bald cypress in Florida, and pond cypress in Florida. The levels of genetic differentiation among the groups were low but significant. Several loci showed the signatures of positive selection, which might be responsible for local adaptation or varietal differentiation. CONCLUSIONS: Bald cypress was genetically differentiated into two geographical groups, and the boundary was located between the MRAV and Florida. This differentiation could be explained by population expansion from east to west. Despite the overlap of the two varieties’ ranges, they were genetically differentiated in Florida. The estimated demographic parameters suggested that pond cypress split from bald cypress during the late Miocene.

American Journal of Botany↗
USGS1999

Seismic hazard map of North and Central America and the Caribbean

Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. National, state, and local government, decision makers, engineers, planners, emergency response organizations, builders, universities, and the general public require seismic hazard estimates for land use planning, improved building design and construction (including adoption of building construction codes), emergency response preparedness plans, economic forecasts, housing and employment decisions, and many more types of risk mitigation. The seismic hazard map of North and Central America and the Caribbean is the concatenation of various national and regional maps, involving a suite of approaches. The combined maps and documentation provide a useful regional seismic hazard framework and serve as a resource for any national or regional agency for further detailed studies applicable to their needs. This seismic hazard map depicts Peak Ground Acceleration (PGA) with a 10% chance of exceedance in 50 years. PGA, a short-period ground motion parameter that is proportional to force, is the most commonly mapped ground motion parameter because current building codes that include seismic provisions specify the horizontal force a building should be able to withstand during an earthquake. This seismic hazard map of North and Central America and the Caribbean depicts the likely level of short-period ground motion from earthquakes in a fifty-year window. Short-period ground motions effect short-period structures (e.g., one-to-two story buildings). The highest seismic hazard values in the region generally occur in areas that have been, or are likely to be, the sites of the largest plate boundary earthquakes.

Annals of Geophysics↗
USGS2007

Mammals of South America, Volume 1, Marsupials, Xenarthrans, Shrews, and Bats

The vast terrain between Panama and Tierra del Fuego contains some of the world?s richest mammalian fauna, but until now it has lacked a comprehensive systematic reference to the identification, distribution, and taxonomy of its mammals. The first such book of its kind and the inaugural volume in a three-part series, Mammals of South America both summarizes existing information and encourages further research of the mammals indigenous to the region. Containing identification keys and brief descriptions of each order, family, and genus, the first volume of Mammals of South America covers marsupials, shrews, armadillos, sloths, anteaters, and bats. Species accounts include taxonomic descriptions, synonymies, keys to identification, distributions with maps and a gazetteer of marginal localities, lists of recognized subspecies, brief summaries of natural history information, and discussions of issues related to taxonomic interpretations. Highly anticipated and much needed, this book will be a landmark contribution to mammalogy, zoology, tropical biology, and conservation biology.

Book↗
USGS1996

Systematics of wolves in eastern North America

Cranial morphology of Recent wolves throughout northern and western North America is remarkably consistent. Statistical analysis indicates the presence of four subspecies of gray wolf (Canis lupus) there, which are always distinguishable from the sympatric coyote (C. latrans). A fifth gray wolf subspecies, lycaon, occurs in southeastern Canada, and the red wolf (C. rufus), is found in the southeast. During the early 1900s the coyote moved east of the prairies and hybridized with the native wolves, thereby creating much confusion. Nonetheless, analysis of every available specimen of wild Canis, dating from before the coyote invasion in the region east of the Mississippi River and south of Wisconsin, Michigan, and New York, does indicate the presence of a small wolf, distinct from the coyote and showing the statistical consistency of other wolf populations. That series also has close affinity to specimens of the red wolf collected in Louisiana and Missouri prior to 1925, and to Pleistocene fossils from the east. There was a sharp line of morphological distinction between the wolves of the eastern United States and those of the prairies, but a closer approach by the former to the subspecies lycaon, which in turn intergrades with gray wolf populations in western Ontario and Minnesota. Although gaps in our knowledge remain, a reasonable hypothesis is that the entire forested region from southeastern Canada to the Gulf Coast originally was inhabited by populations of small wolves, with a subspecific or specific line just south of the eastern Great Lakes. There is no evidence that southeastern North America ever was occupied by large gray wolves and coyotes that hybridized to form the red wolf.

Book chapter↗
USGS1985

An overview of raptor biology and conservation in Latin America

Prior to the last decade, biological studies of raptorial birds in Latin America were, with a few exceptions, nonexistent. For many species all that was known was the general range and habitat type. While the logistical and political challenges are still present, the last few years has seen the opening of a door to what will almost surely be a flood of scientific investigations. From over 40,000 ground miles traveled in 16 countries, field contact with over two thirds of the raptor species, and interviews with conservation officers in 10 nations, I will report on some raptor concentration areas, identify topics for future research, and generalize on raptor conservation issues. I will also briefly mention some recent biological studies and touch briefly on the challenges awaiting the biologist who tries his or her hand at reaping the rewards that are present in abundance for those who engage in raptor studies in Latin America.

Book chapter↗
USGS1990

Raptor road surveys in South America

Twenty-six (23 traveling and three point) raptor roadside surveys were conducted during a 29,000 km expedition through nine nations of South America. During roadside surveys, we tallied 41 of the 87 (47%) diurnal raptor species (including vultures) that occur in South America. The number of species observed per route varied from 17 in the wet savanna of Venezuela to only two species recorded in the harsh Atacama Desert and the dry montane grasslands of Chile and Peru. Raptor density (non-vultures) varied from 1 per 67 km in the Atacama Desert to more than 1 per km in agricultural areas where caracaras and other species that utilize disturbed habitats were common. Responses of raptor communities to deforestation and other habitat disturbances are discussed. While certain habitat modifications potentially increase raptor abundance and diversity, the alteration of primary forest has the opposite effect, at least on diversity.

Journal of Raptor Research↗
USGS1986

An overview of raptor conservation in Latin America

Prior to the last decade, biological studies of raptorial birds in Latin America were almost nonexistent. For many species little more was known than their general range and habitat type. The last few years have seen the opening of a door to what will surely be a flood of scientific investigations. Ultimately, the survival of raptor communities in Latin America depends not only on research but also on several other equally significant conservation efforts. These typically appear in the following order: first, appropriate legislation must be enacted and enforced to provide legal protection; second, the public must be educated concerning the value of wildlife; third, substantial blocks of favourable habitat must be identified and preserved; fourth, economic incentives must be generated so that the local human populations actually benefit from the preservation of vulnerable wildlife and natural habitats; and finally, the long-term success of all of these efforts in each nation depends on the attainment of political, economic and social stability.

Birds of Prey Bulletin↗
USGS1977

Conservation committee report. Falconry: Effects on raptor populations and management in North America

The art of falconry in North America, practiced by a few individuals for many years, attracted little attention until the 1960?s. Presently about 2800 falconers are licensed in the United States with less than one half considered to be active. While interest in this art is expected to increase, we believe growth will be slow, probably 5 to 10% per year, due to rigorous demands on time and equipment required and restrictive regulations.....Many different species of raptors have been used in falconry. Presently 6 species are commonly used, especially the Red-tailed Hawk and American Kestrel. Present evidence suggests that only 2 races of the Peregrine Falcon are threatened in North America, and declines may have occurred in local populations of other species. Declines in populations of Peregrines are attributed to pesticide contamination of food chains. Apparent declines in other populations of raptors are also attributed to pesticides and locally to changes in land use and possibly indiscriminate shooting. Removal of raptors from wild populations for falconry has not had documentable adverse effects except possibly at local nesting sites. Continuation of the art of falconry under the framework of the recent federal regulations is not expected to have measurable impacts on region-wide populations. Management of raptors is poorly developed and relatively unexplored. Captive breeding of raptors holds much promise for production of birds both for re-establishment and as a source of birds for falconry. Falconers have contributed much to the continued improvement of the Cornell University Peregrine program in terms of breeding stocks and technique development.

The Wilson Bulletin↗
USGS2010

Thermal state of permafrost in North America: A contribution to the international polar year

A snapshot of the thermal state of permafrost in northern North America during the International Polar Year (IPY) was developed using ground temperature data collected from 350 boreholes. More than half these were established during IPY to enhance the network in sparsely monitored regions. The measurement sites span a diverse range of ecoclimatic and geological conditions across the continent and are at various elevations within the Cordillera. The ground temperatures within the discontinuous permafrost zone are generally above -3°C, and range down to -15°C in the continuous zone. Ground temperature envelopes vary according to substrate, with shallow depths of zero annual amplitude for peat and mineral soils, and much greater depths for bedrock. New monitoring sites in the mountains of southern and central Yukon suggest that permafrost may be limited in extent. In concert with regional air temperatures, permafrost has generally been warming across North America for the past several decades, as indicated by measurements from the western Arctic since the 1970s and from parts of eastern Canada since the early 1990s. The rates of ground warming have been variable, but are generally greater north of the treeline. Latent heat effects in the southern discontinuous zone dominate the permafrost thermal regime close to 0°C and allow permafrost to persist under a warming climate. Consequently, the spatial diversity of permafrost thermal conditions is decreasing over time.

Permafrost and Periglacial Processes↗
USGS1996

Large-magnitude Middle Ordovician volcanic ash falls in North America and Europe: Dimensions, emplacement and post-emplacement characteristics

Middle Ordovician K-bentonites represent some of the largest known fallout ash deposits in the Phanerozoic Era. They cover minimally 2.2 ?? 106 km2 in eastern North America and 6.9 ?? 105 km2 in northwestern Europe, and represents the coeval accumulation of plinian and co-ignimbrite ash on both Laurentia and Baltica during the closure of the Iapetus Ocean. The three most widespread beds are the Deicke and Millbrig K-bentonites in North America and the Kinnekulle K-bentonite in northwestern Europe. The vents were located near the Laurentian margin of Iapetus on an arc or microplate undergoing collision with Laurentia. The volume of ash preserved in the stratigraphic record converted to dense rock equivalent (DRE) of silicic magma is minimally estimated to be 943 km3 for the Deicke, 1509 km3 for the Millbrig and 972 km3 for the Kinnekulle. The Millbrig and Kinnekulle beds are coeval and possibly equivalent, yielding a combined DRE volume of nearly 2500 km3. Some unknown but probably large amount of additional ash fell into oceanic regions of the Iapetus, but these areas became subducted and the ash is not preserved in the geologic record. The symmetry of the thickness contours is suggestive that one or more ash clouds interacting with equatorial stratospheric and tropospheric wind patterns dispersed pyroclastic material to both the northwest and southeast in terms of Ordovician paleogeography. Based on grain size measurements and thickness/area1/2 plots we conclude the three beds were each formed from co-ignimbrite or possibly phreatoplinian eruption columns. Analyses of melt inclusions in primary quartz crystals indicate the parental magma contained approximately 4% dissolved water at the time of the eruption. This water provided the explosive energy during the initial gas thrust phase. The implied fragmentation pressure on the magma would have reduced much of the ejecta to small particles, forming a deposit composed largely of single crystals and glassy dust. Conversion of the ash to K-bentonite resulted in a mass loss of approximately 35%, mostly in the form of Si with lesser amounts of Na and K.

Journal of Volcanology and Geothermal Research↗
USGS1998

Decadal variability of precipitation over Western North America

Decadal (>7- yr period) variations of precipitation over western North America account for 20%-50% of the variance of annual precipitation. Spatially, the decadal variability is broken into several regional [O(1000 km)] components. These decadal variations are contributed by fluctuations in precipitation from seasons of the year that vary from region to region and that are not necessarily concentrated in the wettest season(s) alone. The precipitation variations are linked to various decadal atmospheric circulation and SST anomaly patterns where scales range from regional to global scales and that emphasize tropical or extratropical connections, depending upon which precipitation region is considered. Further, wet or dry decades are associated with changes in frequency of at least a few short-period circulation 'modes' such as the Pacific-North American pattern. Precipitation fluctuations over the southwestern United States and the Saskatchewan region of western Canada are associated with extensive shifts of sea level pressure and SST anomalies, suggesting that they are components of low-frequency precipitation variability from global-scale climate proceses. Consistent with the global scale of its pressure and SST connection, the Southwest decadal precipitation is aligned with opposing precipitation fluctuations in northern Africa.Decadal (>7-yr period) variations of precipitation over western North America account for 20%-50% of the variance of annual precipitation. Spatially, the decadal variability is broken into several regional [O(1000 km)] components. These decadal variations are contributed by fluctuations in precipitation from seasons of the year that vary from region to region and that are not necessarily concentrated in the wettest season(s) alone. The precipitation variations are linked to various decadal atmospheric circulation and SST anomaly patterns where scales range from regional to global scales and that emphasize tropical or extratropical connections, depending upon which precipitation region is considered. Further, wet or dry decades are associated with changes in frequency of at least a few short-period circulation `modes' such as the Pacific-North American pattern. Precipitation fluctuations over the southwestern United States and the Saskatchewan region of western Canada are associated with extensive shifts of sea level pressure and SST anomalies, suggesting that they are components of low-frequency precipitation variability from global-scale climate processes. Consistent with the global scale of its pressure and SST connection, the Southwest decadal precipitation is aligned with opposing precipitation fluctuations in northern Africa.

Journal of Climate↗
USGS1978

The metallogenic role of east-west fracture zones in South America with regard to the motion of lithospheric plates (with an example from Brazil)

The role of east-west fracture zones in South America is discussed with regard to global fracturing and the motion of lithospheric plates. A set of major NW-trending lineaments has been derived which show a tendency to be spaced equidistantly and may correspond to a set of east-west fractures in the "pre-drift" position of the South American plate. Statistical analysis of linears in the ERTS-mosaics shows that NW-fractures are also among the most important ones in the Andes region, suggesting that the above major lineaments extend into the basement of the Andes. Some of the old major fractures, trending east-west in the present orientation of South America, are discussed and their NE orientation in the pre-drift position of the plate is considered. An example of structural control of ore deposition in the Brazilian Shield is presented, using the maps of the RADAM Project. It is concluded that the small tin-bearing granitic bodies concentrated in the region of Sao Felix do Xingu in the state of Para represent upper parts of an unexposed granitoid massif which is controlled by the intersection of a major east-west fracture zone probably represents westward extension of the Patos Lineament of the easternmost part of Brazil, connected with the east-west fracture zone of the Para state through the basement of the Maranhao Basin (Sineclise do Maranhao-Piaui). It is expected that the proposed "Patos-Para Lineament" extends further westward and may similarly control, at intersections with fractures of other trends, some mineralization centers in the western part of the state of Para and in the state of Amazonas.

South America↗
USGS2008

Gathering, organizing, and accessing data for use in bird conservation across the Americas

The U.S. North American Bird Conservation Initiative (NABCI) Monitoring Subcommittee (2007) identified the need for a comprehensive plan for integrating and managing bird population monitoring data, and to adapt this as an integral component for improving monitoring activities across North America. While the Subcommittee provided a basic framework to begin development of this data management strategy, input from stakeholders is needed to identify data management needs and the technical capacity necessary to solve those challenges. We organized a session at the Fourth International Partners in Flight Conference to solicit input from session participants from across the Americas and identify their data management needs. Session speakers and participants provided examples of the challenges encountered with data management and how the Internet is increasingly used to provide access to the data needed for bird conservation decisions. Input provided during the session indicated that data management needs extended beyond technology to include scientifi c, conservation, social, institutional, and cultural issues. Because data management is intricately related to all aspects of bird conservation, a coordination process that elevates the importance of data management within the bird conservation community is needed, in addition to improving data management associated with bird population monitoring programs. Development of a comprehensive data management strategy for bird population monitoring data would help address the needs and challenges identified during this session.

Conference Paper↗
USGS2007

Presence and significance of chytrid fungus Batrachochytrium dendrobatidis and other amphibian pathogens at warm-water fish hatcheries in southeastern North America

Amphibian populations and species are declining or disappearing from many regions throughout the world (Stuart et al. 2004). No single cause has been demonstrated, although a number of emerging infectious diseases have been suggested as primary etiologic agents (Berger et al. 1998; Daszak et al. 2003; Lips et al. 2006). Several factors, including climate change, parasite infestation or compromised immune systems may interact locally or regionally to threaten species and populations (Carey and Bryant 1995; Parris and Beaudoin 2004; Pounds et al. 2006). Still, the disease model of amphibian decline may not be universally applicable (Daszak et al. 2005; McCallum 2005). The impacts of disease can devastate anuran populations, and declines due to disease, particularly amphibian chytrid fungus (Batrachochytrium dendrobatidis, “BD”) and ranaviruses (Berger et al. 1998; Chinchar 2002), are well documented (Daszak et al. 2003; Kiesecker et al. 2004). In addition to the better-known fungi and viruses, an undescribed Perkinsus-like organism also has had serious localized effects on populations of ranid frogs in southeastern North America (e.g. Rana sevosa in Mississippi, various Florida species; unpublished data). In North America, warm water fish hatcheries supply stock for sport fishing, ecological restoration, and endangered species management. Several million fish may be transported across multiple regions and river drainages in a single restocking event. For example, in 2004 three million bluegill (Lepomis macrochirus), originating from Orangeburg National Fish Hatchery (NFH), South Carolina were stocked at Harris Neck National Wildlife Refuge (NWR), Georgia as food for a nesting colony of endangered wood storks. This stocking in 2004 transported fish from the upper coastal plain across the Savannah River to the lower coastal plain, and may be responsible for mixing different larval phenotypes of Rana catesbeiana at Harris Neck (Dodd and Barichivich 2007). Our objective was to determine whether diseases known to have detrimental effects on amphibians (ranavirus, BD, mesomycetozoa, protozoa and helminths) are present in amphibian larvae living in warm-water fish hatcheries in the southeastern United States. We further examined hatchery records to assess the extent to which amphibian larvae have been transported throughout various regions and potentially contribute to spreading emerging infectious diseases.

Alabama, Florida, Georgia, North Carolina, South C↗
USGS2015

Book review: Bumble bees of North America

Bumblebee identification is generally considered straightforward, yet mistakes often are made due to the degree of similarity between the color patterns of different species. Bumble Bees of North America aims to improve the accuracy of identifications by both casual observers and professionals through the use of intuitive diagrams, descriptions, and the more technical dichotomous keys. In addition to providing the first complete field guide to North American bumblebees, the authors make efficient use of the reader’s attention by summarizing taxonomic history, favored food plants, and environmental issues concerning bumblebees. Review info: Bumble Bees of North America: An Identification Guide. By Paul H. Williams, Robbin W. Thorp, Leif L. Richardson & Sheila R. Colla, 2014. ISBN: 978-0691152226, 208 pp.

The Prairie Naturalist↗
USGS2016

Book review: Ducks, geese, and swans of North America

As pointed out in the book’s introduction by Richard McCabe, very few books deserve being called a classic. First published in 1942, the various editions of Ducks, Geese, and Swans of North America—authored by Francis K. Kortright (1942), Frank C. Bellrose (1976, 1981), and this new edition by Guy Baldassarre (2014)—are deservedly placed in that category among the waterfowl literature. This book has been a valuable resource for the scientific community and waterfowl enthusiasts, and I was excited to learn that a new version has been published. As expected, this new edition did not disappoint and is a remarkable volume in terms of incorporating current research into each species account in a way that does not overwhelm either professional or amateur readers. Review info: Ducks, geese, and swans of North America. By Guy Baldassarre, 2014. ISBN: 978-1421407517, 1088 pp.

Prairie Naturalist↗